Floating versus offshore wind turbines: a comparative life cycle assessment

The technology and utilisation of wind energy systems is growing rapidly. The floating wind turbine system is a large-scale power plant and state-of-the-art technology. However, the environmental impacts of such a system should be considered and compared to that of onshore and offshore wind energy systems. The environmental impact of the barge-type floating wind turbines is investigated using life cycle assessment methodology and comparing data between onshore, offshore and floating wind turbines. The foundation of the floating is square, ring-shaped (open in its centre) and connected to the seabed with synthetic fibre-nylon rope and an anchorage system. The manufacture, operation, disposal and recycling stages of the wind turbine have been evaluated. For the barge-type floating wind turbine, it has been found that the largest environmental impact comes from the manufacturing stage. Global warming potential and energy payback time of the barge-type floating wind turbine is higher than onshore, offshore (2MW) and floating (5MW) wind turbines. Global warming potential of the barge-type floating wind turbine was found 18.6 gCO₂eq./kWh. Moreover, it has been found that the recycling stage is a positive contribution in terms of environmental impact.